Picture frame



FIG. 1 is a front perspective view of a picture frame showing my new design;

FIG. 2 is a rear perspective view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a rear elevational view thereof;

FIG. 5 is a top plan view thereof;

FIG. 6 is a bottom view thereof; and

FIG. 7 is a left side elevational view thereof, the opposite side being a mirror image. 

The ornamental design for a picture frame, as shown and described. 